[thirdparty/glibc.git] / sysdeps / ieee754 / ldbl-128 / k_sincosl.c

/* Quad-precision floating point sine and cosine on <-pi/4,pi/4>.
   Copyright (C) 1999-2015 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Jakub Jelinek <jj@ultra.linux.cz>

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, see
   <http://www.gnu.org/licenses/>.  */

#include <float.h>
#include <math.h>
#include <math_private.h>

static const long double c[] = {
#define ONE c[0]
 1.00000000000000000000000000000000000E+00L, /* 3fff0000000000000000000000000000 */

/* cos x ~ ONE + x^2 ( SCOS1 + SCOS2 * x^2 + ... + SCOS4 * x^6 + SCOS5 * x^8 )
   x in <0,1/256>  */
#define SCOS1 c[1]
#define SCOS2 c[2]
#define SCOS3 c[3]
#define SCOS4 c[4]
#define SCOS5 c[5]
-5.00000000000000000000000000000000000E-01L, /* bffe0000000000000000000000000000 */
 4.16666666666666666666666666556146073E-02L, /* 3ffa5555555555555555555555395023 */
-1.38888888888888888888309442601939728E-03L, /* bff56c16c16c16c16c16a566e42c0375 */
 2.48015873015862382987049502531095061E-05L, /* 3fefa01a01a019ee02dcf7da2d6d5444 */
-2.75573112601362126593516899592158083E-07L, /* bfe927e4f5dce637cb0b54908754bde0 */

/* cos x ~ ONE + x^2 ( COS1 + COS2 * x^2 + ... + COS7 * x^12 + COS8 * x^14 )
   x in <0,0.1484375>  */
#define COS1 c[6]
#define COS2 c[7]
#define COS3 c[8]
#define COS4 c[9]
#define COS5 c[10]
#define COS6 c[11]
#define COS7 c[12]
#define COS8 c[13]
-4.99999999999999999999999999999999759E-01L, /* bffdfffffffffffffffffffffffffffb */
 4.16666666666666666666666666651287795E-02L, /* 3ffa5555555555555555555555516f30 */
-1.38888888888888888888888742314300284E-03L, /* bff56c16c16c16c16c16c16a463dfd0d */
 2.48015873015873015867694002851118210E-05L, /* 3fefa01a01a01a01a0195cebe6f3d3a5 */
-2.75573192239858811636614709689300351E-07L, /* bfe927e4fb7789f5aa8142a22044b51f */
 2.08767569877762248667431926878073669E-09L, /* 3fe21eed8eff881d1e9262d7adff4373 */
-1.14707451049343817400420280514614892E-11L, /* bfda9397496922a9601ed3d4ca48944b */
 4.77810092804389587579843296923533297E-14L, /* 3fd2ae5f8197cbcdcaf7c3fb4523414c */

/* sin x ~ ONE * x + x^3 ( SSIN1 + SSIN2 * x^2 + ... + SSIN4 * x^6 + SSIN5 * x^8 )
   x in <0,1/256>  */
#define SSIN1 c[14]
#define SSIN2 c[15]
#define SSIN3 c[16]
#define SSIN4 c[17]
#define SSIN5 c[18]
-1.66666666666666666666666666666666659E-01L, /* bffc5555555555555555555555555555 */
 8.33333333333333333333333333146298442E-03L, /* 3ff81111111111111111111110fe195d */
-1.98412698412698412697726277416810661E-04L, /* bff2a01a01a01a01a019e7121e080d88 */
 2.75573192239848624174178393552189149E-06L, /* 3fec71de3a556c640c6aaa51aa02ab41 */
-2.50521016467996193495359189395805639E-08L, /* bfe5ae644ee90c47dc71839de75b2787 */

/* sin x ~ ONE * x + x^3 ( SIN1 + SIN2 * x^2 + ... + SIN7 * x^12 + SIN8 * x^14 )
   x in <0,0.1484375>  */
#define SIN1 c[19]
#define SIN2 c[20]
#define SIN3 c[21]
#define SIN4 c[22]
#define SIN5 c[23]
#define SIN6 c[24]
#define SIN7 c[25]
#define SIN8 c[26]
-1.66666666666666666666666666666666538e-01L, /* bffc5555555555555555555555555550 */
 8.33333333333333333333333333307532934e-03L, /* 3ff811111111111111111111110e7340 */
-1.98412698412698412698412534478712057e-04L, /* bff2a01a01a01a01a01a019e7a626296 */
 2.75573192239858906520896496653095890e-06L, /* 3fec71de3a556c7338fa38527474b8f5 */
-2.50521083854417116999224301266655662e-08L, /* bfe5ae64567f544e16c7de65c2ea551f */
 1.60590438367608957516841576404938118e-10L, /* 3fde6124613a811480538a9a41957115 */
-7.64716343504264506714019494041582610e-13L, /* bfd6ae7f3d5aef30c7bc660b060ef365 */
 2.81068754939739570236322404393398135e-15L, /* 3fce9510115aabf87aceb2022a9a9180 */
};

#define SINCOSL_COS_HI 0
#define SINCOSL_COS_LO 1
#define SINCOSL_SIN_HI 2
#define SINCOSL_SIN_LO 3
extern const long double __sincosl_table[];

void
__kernel_sincosl(long double x, long double y, long double *sinx, long double *cosx, int iy)
{
  long double h, l, z, sin_l, cos_l_m1;
  int64_t ix;
  u_int32_t tix, hix, index;
  GET_LDOUBLE_MSW64 (ix, x);
  tix = ((u_int64_t)ix) >> 32;
  tix &= ~0x80000000;			/* tix = |x|'s high 32 bits */
  if (tix < 0x3ffc3000)			/* |x| < 0.1484375 */
    {
      /* Argument is small enough to approximate it by a Chebyshev
	 polynomial of degree 16(17).  */
      if (tix < 0x3fc60000)		/* |x| < 2^-57 */
	{
	  if (fabsl (x) < LDBL_MIN)
	    {
	      long double force_underflow = x * x;
	      math_force_eval (force_underflow);
	    }
	  if (!((int)x))			/* generate inexact */
	    {
	      *sinx = x;
	      *cosx = ONE;
	      return;
	    }
	}
      z = x * x;
      *sinx = x + (x * (z*(SIN1+z*(SIN2+z*(SIN3+z*(SIN4+
			z*(SIN5+z*(SIN6+z*(SIN7+z*SIN8)))))))));
      *cosx = ONE + (z*(COS1+z*(COS2+z*(COS3+z*(COS4+
		     z*(COS5+z*(COS6+z*(COS7+z*COS8))))))));
    }
  else
    {
      /* So that we don't have to use too large polynomial,  we find
	 l and h such that x = l + h,  where fabsl(l) <= 1.0/256 with 83
	 possible values for h.  We look up cosl(h) and sinl(h) in
	 pre-computed tables,  compute cosl(l) and sinl(l) using a
	 Chebyshev polynomial of degree 10(11) and compute
	 sinl(h+l) = sinl(h)cosl(l) + cosl(h)sinl(l) and
	 cosl(h+l) = cosl(h)cosl(l) - sinl(h)sinl(l).  */
      index = 0x3ffe - (tix >> 16);
      hix = (tix + (0x200 << index)) & (0xfffffc00 << index);
      if (signbit (x))
	{
	  x = -x;
	  y = -y;
	}
      switch (index)
	{
	case 0: index = ((45 << 10) + hix - 0x3ffe0000) >> 8; break;
	case 1: index = ((13 << 11) + hix - 0x3ffd0000) >> 9; break;
	default:
	case 2: index = (hix - 0x3ffc3000) >> 10; break;
	}

      SET_LDOUBLE_WORDS64(h, ((u_int64_t)hix) << 32, 0);
      if (iy)
	l = y - (h - x);
      else
	l = x - h;
      z = l * l;
      sin_l = l*(ONE+z*(SSIN1+z*(SSIN2+z*(SSIN3+z*(SSIN4+z*SSIN5)))));
      cos_l_m1 = z*(SCOS1+z*(SCOS2+z*(SCOS3+z*(SCOS4+z*SCOS5))));
      z = __sincosl_table [index + SINCOSL_SIN_HI]
	  + (__sincosl_table [index + SINCOSL_SIN_LO]
	     + (__sincosl_table [index + SINCOSL_SIN_HI] * cos_l_m1)
	     + (__sincosl_table [index + SINCOSL_COS_HI] * sin_l));
      *sinx = (ix < 0) ? -z : z;
      *cosx = __sincosl_table [index + SINCOSL_COS_HI]
	      + (__sincosl_table [index + SINCOSL_COS_LO]
		 - (__sincosl_table [index + SINCOSL_SIN_HI] * sin_l
		    - __sincosl_table [index + SINCOSL_COS_HI] * cos_l_m1));
    }
}
Commit	Line	Data
3fe4dc41	1	/* Quad-precision floating point sine and cosine on <-pi/4,pi/4>.
b168057a	2	Copyright (C) 1999-2015 Free Software Foundation, Inc.
3fe4dc41 UD	3	This file is part of the GNU C Library.
	4	Contributed by Jakub Jelinek <jj@ultra.linux.cz>
	5
	6	The GNU C Library is free software; you can redistribute it and/or
41bdb6e2 AJ	7	modify it under the terms of the GNU Lesser General Public
	8	License as published by the Free Software Foundation; either
	9	version 2.1 of the License, or (at your option) any later version.
3fe4dc41 UD	10
	11	The GNU C Library is distributed in the hope that it will be useful,
	12	but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
41bdb6e2	14	Lesser General Public License for more details.
3fe4dc41	15
41bdb6e2	16	You should have received a copy of the GNU Lesser General Public
59ba27a6 PE	17	License along with the GNU C Library; if not, see
59ba27a6 PE	18	<http://www.gnu.org/licenses/>. */
3fe4dc41	19
ad39cce0	20	#include <float.h>
1ed0291c RH	21	#include <math.h>
1ed0291c RH	22	#include <math_private.h>
3fe4dc41 UD	23
	24	static const long double c[] = {
	25	#define ONE c[0]
	26	1.00000000000000000000000000000000000E+00L, /* 3fff0000000000000000000000000000 */
	27
	28	/* cos x ~ ONE + x^2 ( SCOS1 + SCOS2 * x^2 + ... + SCOS4 * x^6 + SCOS5 * x^8 )
	29	x in <0,1/256> */
	30	#define SCOS1 c[1]
	31	#define SCOS2 c[2]
	32	#define SCOS3 c[3]
	33	#define SCOS4 c[4]
	34	#define SCOS5 c[5]
	35	-5.00000000000000000000000000000000000E-01L, /* bffe0000000000000000000000000000 */
	36	4.16666666666666666666666666556146073E-02L, /* 3ffa5555555555555555555555395023 */
	37	-1.38888888888888888888309442601939728E-03L, /* bff56c16c16c16c16c16a566e42c0375 */
	38	2.48015873015862382987049502531095061E-05L, /* 3fefa01a01a019ee02dcf7da2d6d5444 */
	39	-2.75573112601362126593516899592158083E-07L, /* bfe927e4f5dce637cb0b54908754bde0 */
	40
	41	/* cos x ~ ONE + x^2 ( COS1 + COS2 * x^2 + ... + COS7 * x^12 + COS8 * x^14 )
	42	x in <0,0.1484375> */
	43	#define COS1 c[6]
	44	#define COS2 c[7]
	45	#define COS3 c[8]
	46	#define COS4 c[9]
	47	#define COS5 c[10]
	48	#define COS6 c[11]
	49	#define COS7 c[12]
	50	#define COS8 c[13]
	51	-4.99999999999999999999999999999999759E-01L, /* bffdfffffffffffffffffffffffffffb */
	52	4.16666666666666666666666666651287795E-02L, /* 3ffa5555555555555555555555516f30 */
	53	-1.38888888888888888888888742314300284E-03L, /* bff56c16c16c16c16c16c16a463dfd0d */
	54	2.48015873015873015867694002851118210E-05L, /* 3fefa01a01a01a01a0195cebe6f3d3a5 */
	55	-2.75573192239858811636614709689300351E-07L, /* bfe927e4fb7789f5aa8142a22044b51f */
	56	2.08767569877762248667431926878073669E-09L, /* 3fe21eed8eff881d1e9262d7adff4373 */
	57	-1.14707451049343817400420280514614892E-11L, /* bfda9397496922a9601ed3d4ca48944b */
	58	4.77810092804389587579843296923533297E-14L, /* 3fd2ae5f8197cbcdcaf7c3fb4523414c */
	59
	60	/* sin x ~ ONE * x + x^3 ( SSIN1 + SSIN2 * x^2 + ... + SSIN4 * x^6 + SSIN5 * x^8 )
	61	x in <0,1/256> */
	62	#define SSIN1 c[14]
	63	#define SSIN2 c[15]
	64	#define SSIN3 c[16]
	65	#define SSIN4 c[17]
	66	#define SSIN5 c[18]
	67	-1.66666666666666666666666666666666659E-01L, /* bffc5555555555555555555555555555 */
	68	8.33333333333333333333333333146298442E-03L, /* 3ff81111111111111111111110fe195d */
	69	-1.98412698412698412697726277416810661E-04L, /* bff2a01a01a01a01a019e7121e080d88 */
	70	2.75573192239848624174178393552189149E-06L, /* 3fec71de3a556c640c6aaa51aa02ab41 */
	71	-2.50521016467996193495359189395805639E-08L, /* bfe5ae644ee90c47dc71839de75b2787 */
	72
	73	/* sin x ~ ONE * x + x^3 ( SIN1 + SIN2 * x^2 + ... + SIN7 * x^12 + SIN8 * x^14 )
	74	x in <0,0.1484375> */
	75	#define SIN1 c[19]
	76	#define SIN2 c[20]
	77	#define SIN3 c[21]
	78	#define SIN4 c[22]
	79	#define SIN5 c[23]
	80	#define SIN6 c[24]
	81	#define SIN7 c[25]
	82	#define SIN8 c[26]
	83	-1.66666666666666666666666666666666538e-01L, /* bffc5555555555555555555555555550 */
	84	8.33333333333333333333333333307532934e-03L, /* 3ff811111111111111111111110e7340 */
	85	-1.98412698412698412698412534478712057e-04L, /* bff2a01a01a01a01a01a019e7a626296 */
	86	2.75573192239858906520896496653095890e-06L, /* 3fec71de3a556c7338fa38527474b8f5 */
87	-2.50521083854417116999224301266655662e-08L, /* bfe5ae64567f544e16c7de65c2ea551f */
88	1.60590438367608957516841576404938118e-10L, /* 3fde6124613a811480538a9a41957115 */
89	-7.64716343504264506714019494041582610e-13L, /* bfd6ae7f3d5aef30c7bc660b060ef365 */
90	2.81068754939739570236322404393398135e-15L, /* 3fce9510115aabf87aceb2022a9a9180 */
91	};
92
93	#define SINCOSL_COS_HI 0
94	#define SINCOSL_COS_LO 1
95	#define SINCOSL_SIN_HI 2
96	#define SINCOSL_SIN_LO 3
97	extern const long double __sincosl_table[];
98
99	void
100	__kernel_sincosl(long double x, long double y, long double sinx, long double cosx, int iy)
101	{
102	long double h, l, z, sin_l, cos_l_m1;
103	int64_t ix;
104	u_int32_t tix, hix, index;
105	GET_LDOUBLE_MSW64 (ix, x);
106	tix = ((u_int64_t)ix) >> 32;
107	tix &= ~0x80000000; /* tix = \|x\|'s high 32 bits */
108	if (tix < 0x3ffc3000) /* \|x\| < 0.1484375 */
109	{
110	/* Argument is small enough to approximate it by a Chebyshev
111	polynomial of degree 16(17). */
112	if (tix < 0x3fc60000) /* \|x\| < 2^-57 */
ad39cce0 JM	113	{
	114	if (fabsl (x) < LDBL_MIN)
	115	{
	116	long double force_underflow = x * x;
	117	math_force_eval (force_underflow);
	118	}
	119	if (!((int)x)) /* generate inexact */
	120	{
	121	*sinx = x;
	122	*cosx = ONE;
	123	return;
	124	}
	125	}
3fe4dc41 UD	126	z = x * x;
	127	sinx = x + (x (z(SIN1+z(SIN2+z(SIN3+z(SIN4+
	128	z(SIN5+z(SIN6+z(SIN7+zSIN8)))))))));
	129	cosx = ONE + (z(COS1+z(COS2+z(COS3+z*(COS4+
	130	z(COS5+z(COS6+z(COS7+zCOS8))))))));
	131	}
	132	else
	133	{
	134	/* So that we don't have to use too large polynomial, we find
	135	l and h such that x = l + h, where fabsl(l) <= 1.0/256 with 83
	136	possible values for h. We look up cosl(h) and sinl(h) in
	137	pre-computed tables, compute cosl(l) and sinl(l) using a
	138	Chebyshev polynomial of degree 10(11) and compute
	139	sinl(h+l) = sinl(h)cosl(l) + cosl(h)sinl(l) and
	140	cosl(h+l) = cosl(h)cosl(l) - sinl(h)sinl(l). */
	141	index = 0x3ffe - (tix >> 16);
	142	hix = (tix + (0x200 << index)) & (0xfffffc00 << index);
c0df8e69 JM	143	if (signbit (x))
	144	{
	145	x = -x;
	146	y = -y;
	147	}
3fe4dc41 UD	148	switch (index)
	149	{
	150	case 0: index = ((45 << 10) + hix - 0x3ffe0000) >> 8; break;
	151	case 1: index = ((13 << 11) + hix - 0x3ffd0000) >> 9; break;
	152	default:
	153	case 2: index = (hix - 0x3ffc3000) >> 10; break;
	154	}
	155
	156	SET_LDOUBLE_WORDS64(h, ((u_int64_t)hix) << 32, 0);
	157	if (iy)
	158	l = y - (h - x);
	159	else
	160	l = x - h;
	161	z = l * l;
	162	sin_l = l(ONE+z(SSIN1+z(SSIN2+z(SSIN3+z(SSIN4+zSSIN5)))));
	163	cos_l_m1 = z(SCOS1+z(SCOS2+z(SCOS3+z(SCOS4+z*SCOS5))));
	164	z = __sincosl_table [index + SINCOSL_SIN_HI]
	165	+ (__sincosl_table [index + SINCOSL_SIN_LO]
	166	+ (__sincosl_table [index + SINCOSL_SIN_HI] * cos_l_m1)
	167	+ (__sincosl_table [index + SINCOSL_COS_HI] * sin_l));
	168	*sinx = (ix < 0) ? -z : z;
	169	*cosx = __sincosl_table [index + SINCOSL_COS_HI]
	170	+ (__sincosl_table [index + SINCOSL_COS_LO]
	171	- (__sincosl_table [index + SINCOSL_SIN_HI] * sin_l
	172	- __sincosl_table [index + SINCOSL_COS_HI] * cos_l_m1));
	173	}
	174	}